Interesting question. Thanks 100011_100001.
I always had a positive mental attitude. Not really sure why. Difficult childhood? Last kid picked in kickball? Couldn't get a date? Knew nobody was ever going to give me a thing so I would have to do it myself? Who knows? Way too much to think about for an answer now, but that's OK because...
My problem wasn't that I didn't have a positive mental attitude.
My problem was that I didn't know I had a positive mental attitude.
I was a typical nerd who found solace in math and programming but somehow worked my way up into a dev / project management / digital rainmaker position. My customer wanted me to do something he knew I could do that no one else had been able to do (something boring sounding like "implementing a factory shop floor control system").
He became so exasperated at my pushback (I can't. It can't be done. It's too hard. etc) that eventually yelled at me something like, "You know the business! You know the tech! You're good with people! You have PMA! So what's the f*in problem?) I asked, "What is PMA?" He said "Positive Mental Attitude!"
That conversation changed my career (and my life). And he became my major mentor. (That's why I thought of him in that "Advice that changed your life" thread last week.
This may sound bizarre and counter-intuitive but I think the short answer to your question may be, "You have PMA when you decide you have PMA."
Over the years, I've witnessed countless counter-examples to this: people don't have PMA because they don't know they have PMA so they never "breakthrough" like they could.
I'm so glad I met that mentor. Thanks for reminding me.
Hope this helps.